The invention relates generally to tee devices for practicing a sport, such as golf, and more particularly to technologies for verifying that a ball is placed on a tee device and for allowing the height of the ball to be easily adjusted.
Tee devices are used in various sports to practice hitting skills. For example, tee devices commonly are used in baseball, softball and golf. Typically, the participant must manually set the ball on the device, but the benefits of a practice sessions are increased if an automated ball supply mechanism is used to replace a ball after each swing.
Often, a detection system is included within an automated ball supply mechanism to confirm that a ball has been placed on a tee device. In a golf practice device for a driving practice range, a reflecting type of photocell may be used. The photocell emits light to a golf ball placed on a tee and receives reflected light. When the reflected light is detected, a ball-confirmation signal is transmitted to a control device, which causes a ball supply arm to reset so as to draw away from the tee. This stops the next ball from being supplied. If the reflected light is not received within a preselected period of time, the photocell system emits a ball-unconfirmed signal to the control device, which then causes the ball supply arm to draw near the tee and supply the next ball. For tee devices that reside below a floor level, the supply operation may also include moving the tee device upwardly and downwardly relative to the floor level.
An alternative golf ball confirmation approach is to connect the tee to a weight sensor or a load sensor. When a golf is placed on the tee, the sensor detects the increase in weight. The sensor then transmits a ball-confirmation signal, similar to the photocell approach. Automated supply operations may be identical to the ones described with reference to the use of the photocell.
While the prior art approaches operate reasonably well for their intended purposes, there are concerns. For example, in a driving range environment, the automated devices are exposed to rain. Moreover, dust accumulates and light may be inadvertently blocked. Another concern is that direct sunlight will reflect off the ball and may lead to false readings by the photocell system. For the weight sensor approach of ball confirmation, malfunctions may occur when the tee is inadvertently touched. Particularly, when a ball is supplied at a level below a floor, there are experiences of malfunctions as a result of age deterioration as the tee is regularly raised and lowered. Resistance from the accumulation of dirt and the like is also a cause of malfunctions. Finally, the weight sensors may be susceptible to false readings as a result of the differences in weights of practice balls and some official balls.
An object of the invention is to provide a key device for sports practice, where the tee device has an automated system with a low susceptibility to malfunctions and false readings. Another object is to provide a tee device that enables mechanized manipulation of ball height.
An automated tee device utilizes air pressure to determine when a next ball should be supplied to a ball-seating end of a tee. The tee includes an air passageway to an outlet at the ball-seating end. The air passageway is connected to a supply of pressurized air which has a pressure that is less than the gravitational force of a ball at rest on the ball-seating end of the tee. In one application, the ball-seating end is configured to support a golf ball. A detector monitors airflow through the air passageway and outputs a signal that is indicative of the current condition of airflow. This signal is transmitted to a controller which triggers automated operations on the basis of the current state of the signal.
The controller may be a central processing unit (CPU) that operates a ball supply mechanism for automatically feeding balls to the ball-seating end of the tee. In some applications, the ball is supplied at a sub-floor level, so that the controller cooperates with the detector to determine when the tee should be lowered to receive the next ball.
The detector may include a movable member having a rest position and a displaced position. The movable member should be located along the airflow path from the airflow supply to the ball-seating end of the tee. The movable member is forced by airflow from its rest position to its displaced position when there is no ball at rest on the ball-seating end. The detector also includes a sensor which monitors the position of the movable member and outputs a signal on the basis of the current position.
The movable member may be a butterfly board that is oriented to inhibit airflow when the butterfly board is in its rest position. However, when a ball is removed from the ball-seating end of the tee, airflow forces the butterfly board to the displaced position. An optical sensor may be used to determine the position of the butterfly board.
As another aspect of the invention, the automated tee device may include a height adjustment system. In accordance with this aspect, the height adjustment system includes a motor connected to the tee to adjust a vertical position of the ball-seating end to any position within a preselected vertical range. An activation switch turns the motor on and off. An upper limit switch is mechanically associated with the tee and electrically associated with the motor to automatically reverse the direction of the motor in response to the ball-seating end reaching an upper vertical limit of the range. Similarly, a lower limit switch is mechanically associated with the tee and electrically associated with the motor to again reverse the direction of the tee adjustment in response to the ball-seating end reaching a lower vertical limit within the range.
An advantage of the invention is that the air pressure detection provides a reliable indication of the presence or absence of a ball on the tee. The ball may be a golf ball, but can also be a baseball, a softball, or the like. Another advantage of the invention is that the automated tee device is easily maintained, since the sensing capability is housed within the airflow path and is therefore not directly exposed to the environment. Another advantage is that the height of a ball can be readily adjusted to fit the preferences of the users.